Oh, movies are startups too. Often you see a production company established to make a single movie. And they spawn clones -- Star Wars gave rise to perhaps hundreds of space movies -- many of them really bad.
It depends on the era. Lucasfilm was definitely a startup during its halcyon days(not just in film, but in FX (special and CGI), editing, and sound design). But most of the prolific movies of the era before Lucasfilm were products of the studio system (or what remained of it) whose operating principles mirrored that of IBM.
